Aging kegged homebrew and co2 PSI setting

[PsychoBrew]

I know this has been covered in another thread, but it does not seem like it was fully answered.

I'm getting ready to keg a batch for the first time. I have seen a youtube video by micromatic saying that you can force carbonate for two days at 33psi and then it is ready to go. I find that a bit hard to take since the beer has not aged at all.

Here is the question - if I age this brew for an additional two to three weeks at room temp (60 degrees) should the PSI stay the same (33psi) or can it be dropped down to something in the area of 12 psi after a couple of days?

[beerking]

If you are trying to force carbonate at higher temperatures, you will need higher PSI values to get the same volume of CO2 in your beer. In fact, it will need to be a LOT higher.

Rounding down your number to 30 PSI, and assuming 32F, you would be pressurizing to 4.77 volumes of CO2. This pressure is only held for two days, which means you will not get that much CO2 into solution. Using 30 PSI at 60F will only give you 2.92 volumes of CO2.

Taking the time into account, the 33 PSI at 32F for 2 days is intended to push the CO2 into solution much quicker than it would at a lower pressure. If we assume you are wanting to carbonate to a more reasonable 2.25 volumes of CO2, you would need to hold a steady pressure of 20 PSI for your extended period at 60F. I have not tried this, but I believe you would have sufficient carbonation in 1 week, certainly by 2. I would not lower the pressure until you chilled the beer, since 20 PSi would be required to maintain your desired carbonation level. 12 PSi at a serving temperature is intended to maintain that 2.25 volumes of CO2.

[PsychoBrew]

Thanks Beerking - thats exactly the kind of info I was looking for. I will force with 20psi for a week or two and then serve at the usual 12ish psi.
I just found a handy little excel calcualtor for this on the net which confirms your figures.

Isnt 2.4 volumes of CO2 kind of the target to shoot for?

[beerking]

That depends very much on the style of beer, and your personal preferences. I tend to prefer my beers a little less carbonated than most, but the range can be as low as 1.5 and as high as 4.5. The different levels for each style are listed at
http://sdcollins.home.mindspring.com/ForceCarbonation.html

[PsychoBrew]

Once again - thanks Beerking, that was great info.
Tested out the keggs tonight and it seems that I have two that need rebuilt, but I have two that hold presure just fine so I will be kegging up a Blonde ale tomorrow night after work.

[cynical_writer]

I was actually coming on here to ask about carbonating and that site beerking posted really helped.

Except that Im looking to carbonate a Cerveza and its not one of the listed styles on there and was wondering if you knew about how many volumes i should carbonate it to?

And how better is it to slowly carbonate than to force carbonate by shaking the kegs?

[PsychoBrew]

Except that Im looking to carbonate a Cerveza and its not one of the listed styles on there and was wondering if you knew about how many volumes i should carbonate it to?


Wouldnt it be close to the American ales and lagers? Since it is on the lighter side much like a blonde or pale.

[beerking]

Yes. I would go with American Ales and Lagers.

Basically, all industrial lager is the same from a base ingredients, and even more from a carbonation perspective (BMC, Singha, Corona, Becks, St. Pauli, Heineken, etc), provided you are comparing the bottled/canned examples (some of those have a different version on draft).